Index: trunk/src/org/openstreetmap/josm/data/osm/Relation.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/osm/Relation.java	(revision 4212)
+++ trunk/src/org/openstreetmap/josm/data/osm/Relation.java	(revision 4213)
@@ -407,5 +407,5 @@
 
     public boolean isMultipolygon() {
-        return "multipolygon".equals(get("type"));
+        return "multipolygon".equals(get("type")) || "boundary".equals(get("type"));
     }